Description
The bones of the pectoral girdle (shoulder girdle) are one of the two groups of bones of the upper limb, the other being the bones of the free part of the upper limb. It consists of the clavicle and scapula, which articulate with each other at the acromioclavicular joint.
Because the pectoral girdle articulates directly with the axial skeleton at the sternoclavicular joint, it’s less mobile than the free part of the upper limb. The pectoral girdle articulates with the free part of the upper limb at the glenohumeral (shoulder) joint.
Overall, the pectoral girdle provides the bony platform for movements of the upper limb and maintains its lateral position relative to the trunk. Unlike the pelvic girdle, the pectoral girdle does not form a complete ring around the axial skeleton and it’s not weight bearing. This allows it to be less stable than the pelvic girdle and, therefore, more mobile.